Dispensing device for liquid and semi-liquid substances



DISPENSING DEVICE FOR LIQUID AND SEMI-LIQUID SUBSTANCES Filed July 8,1965 .Bhnnnn INVENTOE BY 14w; 6%, 440,44 4 a TOEZNEYJ United StatesPatent DISPENSING DEVICE FUR LIQUID AND SEMl-LIQUHD SUBSTANCES PatrickClement Cox, The Pippins, Brimpton, Reading, England Filed July 8, W65,Ser. No. 470,454 Claims priority, application Great Britain, .luly 15,1964, 29,134/6d 1 Qiairn. (Cl. 222-327) This invention relates todispensing devices for liquid or semi-liquid substances, which term isto be understood as including substances or mixtures of substances,which can be caused to flow through the application thereto of manuallyapplied pressure, and is particularly but not exclusively applicable todispensing devices for medicinal or curative purposes, for exampledevices for administrating doses of predetermined volume to farm orother animals.

For convenience, therefore, herein, the term dose will be used to referto a predetermined volume of a liquid or semi-liquid substance deliveredby the dispensing device irrespective of whether the substance isdelivered for medical or for other purposes.

It is an object of the invention to provide a form of dispensing devicefor liquid and semi-liquid substances which, while being of simple form,will readily enable the volume of the dose delivered upon the operationof operating mechanism to be determined with a satisfactory degree ofaccuracy and varied as may be required.

A dispensing device for liquid or semi-liquid substances according tothe present invention comprises a supporting structure, a reservoir forthe substance to be dispensed carried by the supporting structure and inthe form of a piston and cylinder assembly provided with a dischargeopening or passage, operating mechanism arranged to cause axial movementof one of the two members constituting the piston and cylinder assemblyrelatively to the supporting structure and including an actuating memberarranged to move between predetermined points upon actuation of anoperating member and to cause such relative axial movement, andadjusting means comprising relatively rotatable parts provided withinter-engaging screwthreads of predetermined pitch so arranged thattheir relative rotation causes axial movement of the other of the twomembers constituting the piston and cylinder assembly relatively to thesupporting structure.

Preferably the cylinder comprises one of the relatively rotatable partsso that the other of said relatively rotatable parts is rigid with thesupporting structure while the piston is constituted by a free pistonmember disposed within the cylinder, and the actuating member isarranged to move axially of the cylinder and, when moved in theappropriate direction, to act on the piston to move the latter axiallywithin the cylinder. In such a construction the screwthreaded part whichis rigid with the supporting structure is conveniently internallyscrewthreaded and the cylinder conveniently comprises a tubular memberhaving a cylindrical body part from one end of which extends a nozzle ofsmaller diameter than the body part and constituting the dischargepassage, while its other end portion is provided with an externalscrewthread the base diameter of which is not less than the externaldiameter of the unscrewthreaded part of the body part whereby saidunscrewthreaded part of the body part can enter the bore of theinternally screwthreaded part rigid with the supporting structure.

The above reference to a free piston member is to be interpreted asmeaning a piston member which is not attached to the actuating memberbut is arranged to be .acted upon by it so as to be moved in theappropriate i lafiid Patented May 16, 1967 direction, i.e. towards thenozzle, upon operation of the actuating member.

The piston and cylinder assembly of a construction as referred to abovemay be disposable, in which case such piston and cylinder assemblieseach with a filling of material to be dispensed may be supplied in theform of cartridges or refills.

Thus, according to another aspect of the invention a cartridge or refillfor a dispensing device according to the invention comprises a tubularmember having a cylindrical body part provided at one end with anexternal screwthread the base diameter of which is at least equal to theexternal diameter of the unthreaded portion of said body part, whilefrom the other end of said body part projects a nozzle of smallerdiameter than said body part, a free piston disposed within said bodypart so as to make a substantially fluid-tight seal with the boretherefore, and a body of liquid or semi-liquid substance to be dispenseddisposed within the part of said tubular member between the piston andthe exit of the nozzle.

In any event the nozzle of such a cartridge or refill may be closed by aremovable closure member and/or by an automatic valve which will openunder pressure applied to it by the substance Within the cartridge,while the end of the cartridge remote from the nozzle may, in additionto being closed by the piston, be provided with a removable cap orcovering.

Moreover in any case a dispensing device according to the invention willpreferably be provided with indicating means including co-operatingparts or markings respectively on the two relatively rotatable partswhereby an operator can determine when relative rotation between theseparts through a deter-mined angle or any one of a number of determinedangles has been elfected.

Thus a cartridge or refill according to the invention as referred toabove will usually include one or more markings on the outercircumference of the body part for co-operation with a marking orindicator on the part with which it will be brought into screwthreadedengagement when embodied in a dispensing device according to theinvention.

A dispensing device according to the invention is conveniently in theform of a pistol in which the supporting structure includes a handlecorresponding to the stock of the pistol and a tubular internallyscrewthreaded part projecting from the stock in a similar manner to thatof the barrel of the pistol, such tubular part comprising the internallyscrewthreaded part into which extends and from which projects thecylinder, which thus has an external scrcwthread engaging thescrewthread of the internally screwthreaded part, the actuating memberbeing arranged to be moved by a trigger-like operating member againstthe action of a spring.

One construction of dispensing device according to the invention and aform of cartridge or refill according to the invention for usetherewith, together with a modification thereof, are illustrated by wayof example in the accompanying drawings, in which:

FIGURE 1 is a sectional side elevation of the complete dispensingdevice,

FIGURE 2 is a similar view to FIGURE 1 of one form of cartridge orrefill for use with the dispensing device shown in FIGURE 1, and

FIGURE 3 is a cross section on an enlarged scale showing a modificationwhich may be applied to a refill otherwise similar to that shown inFIGURE 2.

In the construction of dispensing device shown in FIG- URE 1 the devicecomprises a supporting structure consisting of a handle 1 formed in twosimilar parts clamped together by bolts, indicated at 2, and a tubularinternally screwt-hreaded part 3 rigidly secured to the handle 2.

The part 3 is connected to the handle 1 by a tubular member 4 formingpart of a guide assembly and provided adjacent to one end (hereinaftercalled its inner end) with an external annular groove in which lies aninternal flange 5 formed in the handle 1 as shown. The extreme inner endof the part 4 thus comprises an external flange 6 as shown. The part 4also includes a part 7 which is externally screwthreaded and engaged bythe inner end portion of the internal screwthread on the tubular part 3.

Extending into and projecting from the outer end of the tubular part 3is a cylinder member comprising a body part 8 having at its inner end anexternal screwthread 9 the base diameter of which is not less than theexternal diameter of the part 8 so that the part 8 can slide and rotatewithin the bore of the tubular part 3 as shown. The end of the cylindermember 8 remote from the screwthread 9 is formed as a nozzle 10, asshown, of smaller diameter than the body part 8, and there is disposedwithin the part 8 a free piston comprising a disc-like part 11 having asmall axially extending flange 12 on one face thereof provided with acircumferential groove in which is disposed a resilient sealing ring 13,for example of the O-ring type.

Extending through the part 7 of the assembly guide is an actuating rod14 which can slide axially relatively to the part 7 and is maintainedsubstantially coaxial with the tubulr part 3 by reason of its making asuitably close sliding fit within a bore in the outer end part 15 of thepart 7 and a bore in a guide socket 16 rigidly secured within the innerend of the bore of the part 7.

Secured, as by two circlips 17, to the outer end of the actuating rod 14is a thrust member 18 arranged to act on the part of the inner face ofthe piston 11 within the flange 12, while a compression spring 19 isinterposed between the inner face of the part 15 and a thrust washer 20on the actuating rod 14 so as to urge the rod 14 always to the left inFIGURE 1. Pivotally connected at 21 to the handle 1 and projecting fromit through a slot 1A is a trigger lever 22 the inner end 23 of which isarranged to act, through a pad 24, on the inner end of the actuating rod14 and is normally held by the spring 19 acting on the rod 14 against astop 25 rigid with the handle.

The trigger lever 22 is, as shown, arranged to be actuated by one ormore fingers of the hand of an operator supporting the device by thehandle 1 so as to move the actuating rod 14 to the right in FIGURE 1from the position shown and this movement is limited by the engagementof the pad 24 with the lefthand face of the guide socket 16. Thus, foreach actuation of the trigger lever 22 by an operator between its twolimiting positions the actuating rod 14, and hence the thrust member 18,moves from one predetermined position to another predetermined position.

When the apparatus is in use the part of the interior of the cylindermember 8 between the end of the nozzle and the adjacent face of thepiston 11 is filled with the substance to be dispensed, and it will beseen that that volume of such substance which will be ejected upon eachoperation of the trigger lever 22 to move the actuating rod 14 betweenits two limiting positions will vary with variations in the distancewhich, before actuation of the trigger lever 22, separates the lefthandface of the piston 11 from the adjacent face of the thrust member 18.For convenience of illustration the parts are shown in the relativepositions they would occupy if it was desired to eject the maximumvolume of material of which the device is capable upon operation of thetrigger lever 22, and it will be apparent that if, with the parts in theposition shown, the trigger lever 22 is actuated and then released so asto eject such maximum quantity, the quantity which will be ejected uponthe next actuation of the trigger lever 22 will depend upon the distancewhich the cylinder member 8 is moved to the left relatively to the part9 by rotation of the part 8 relatively to the part 9 prior to such nextactuation.

It will usually be convenient for the screwthread 9 to be of such pitchthat one complete rotation of the part 8 relatively to the part 9 afteran actuation of the trigger lever 22 will move the part 8 axiallyrelatively to the part 9 somewhat less than the distance which wouldbring the face of the member 18 into engagement with the adjacent faceof the piston 11. Thus, assuming, as would conveniently be the case,that the maximum does which would be used in practice is that resultingfrom one complete rotation of the part 8 relativelyto the part 9, thiswill provide a certain tolerance ensuring against the unintentionalejection of some of the substance through the nozzle 10 by rotation ofthe part 8 slightly further than is required to provide for the ejectionof the maximum dose.

As indicated above, when substantially all the substance has beenejected from the cylinder 8 by the piston 11, apart from a smallremaining amount in the nozzle 10, the assembly consisting of thecylinder member 8 and the piston 11 can be removed from the tubular part3 and disposed of, where upon a new piston and cylinder assemblyconstituting a refill, as shown in FIGURE 2, can be applied to thetubular part 9. As will be apparent this refill comprises a cylinderpart 8 with the appropriate external screwthread 9 at one end and thenozzle 10 at the other, and the piston 11 disposed within its bore andat the position indicated, while the nozzle is closed by a removable cap26 and the chamber within the assembly is substantially filled with thesubstance to be dispensed. The piston in the refill would be disposed insuch position that when the refill is applied to the part 9 and screwedinto this part to a suitable point, indicated for example by acircumferential line the piston would come into or nearly intoengagement with the thrust member 18. The cap 26 would then be removedand the trigger lever 22 actuated so as to eject some of the substance,although since it would not be a predetermined quantity, preferably notfor use as a dose. The apparatus will then be in condition fordispensing measured doses in the manner referred to.

In the modification shown in FIGURE 3 which is a cross section throughthe end portion of the nozzle of a refill otherwise similar to thatshown in FIGURE 2, instead of the end of the nozzle being closed by aclosing cap 26, the nozzle 10 is formed in a manner known per se toprovide an opening surrounded by a flat seating surface 27 inclined tothe axis of the nozzle and normally closed by a flap 28 integral withthe nozzle and constituting a valve which will open under the pressureapplied to it by the substance to be ejected.

There may be assumed to be provided on the outer end of the part 3 ofthe dispensing device shown in FIGURE 1 a mark for example in the formof an arrow or groove, while the exterior surface of the body part 8 inFIGURE 1 and FIGURE 2 is provided with a series of markings in the formof longitudinally extending lines circumferentially spaced from oneanother by predetermined angles so as to indicate, in conjunction withthe marking on the part 3 predetermined angles of rotation which may beimparted to the part 8 relatively to the part 3, these angles ofrotation corresponding to different predetermined doses. Moreover thelongitudinal lines constituting the markings on the part 8 may bearranged to constitute two or more sets, the lines in the different setsbeing differently coloured or otherwise distinguished from one anotherand the lines in each set being equally spaced from one another butdifferently spaced from the lines in each of the other sets. Thus, byemploying lines in one set or another as the indication of the amount ofrotation to be imparted to the member 8 between the delivery ofsuccessive doses, an operator can provide for the delivery in successionof a series of doses each of a determined volume selected from the twoor more volumes to which the sets of lines relate.

What I claim as my invention and desire to secure by Letters Pat ent is:

Apparatus for dosing animals with liquid or semi-liquid substancesincluding a cartridge in the form of a cylinder for the substances to bedispensed having a discharge passage at one end and an externallyscrew-threaded portion at its other end, a free piston arranged to slideWithin the cylinder to eject the substance through the dischargepassage, the base diameter of said screw-threaded part being not lessthan the external diameter of the remaining part of said cylinder, atsupporting structure in the form of a gun having an internallyscrew-threaded barrel portion engaging said screw-threaded portion onthe cylinder whereby rotation of the cylinder relatively to the barrelportion causes axial movement of said cylinder relative to said barrel,an actuating member on said supporting structure and havingpredetermined movement axially of the cylinder independently of butcapable of acting on said free piston, and an operating member arrangedto impart said predetermined axial movement to said actuating member,and a trigger-like member arranged to operate the actuating member.

References Cited by the Examiner UNITED STATES PATENTS 1,039,980 10/1912Lowe 222386 1,870,497 8/1932 Dunlap 222-391 1,870,524 8/1932 McGahey222391 2,102,591 12/1937 Hagerneier 222--386 2,461,211 2/ 1949 Guthrie222326 2,646,90 6 7/1953 Jones et a1 222-327 FOREIGN PATENTS 930,3161/1948 France.

ROBERT B. REEVES, Primary Examiner.

20 HADD S. LANE, Examiner.

